Fairs for e-commerce: the benefits of aggregating buyers and sellers

In recent years, many new and interesting models of successful online business have been developed. Many of these are based on the competition between users, such as online auctions, where the product price is not fixed and tends to rise. Other models, including group-buying, are based on cooperation between users, characterized by a dynamic price of the product that tends to go down. There is not yet a business model in which both sellers and buyers are grouped in order to negotiate on a specific product or service. The present study investigates a new extension of the group-buying model, called fair, which allows aggregation of demand and supply for price optimization, in a cooperative manner. Additionally, our system also aggregates products and destinations for shipping optimization. We introduced the following new relevant input parameters in order to implement a double-side aggregation: (a) price-quantity curves provided by the seller; (b) waiting time, that is, the longer buyers wait, the greater discount they get; (c) payment time, which determines if the buyer pays before, during or after receiving the product; (d) the distance between the place where products are available and the place of shipment, provided in advance by the buyer or dynamically suggested by the system. To analyze the proposed model we implemented a system prototype and a simulator that allow to study effects of changing some input parameters. We analyzed the dynamic price model in fairs having one single seller and a combination of selected sellers. The results are very encouraging and motivate further investigation on this topic

The moderating role of age and seniority on nurses' emotional dissonance and perceived health

This study aims to investigate the weight of surface acting (a condition in which subjects must display an emotional state that does not correspond to their real feelings) in the relationship between the emotional load of nursing work and the perception of health, and to evaluate the moderating effect of age and length of service. A moderated mediation analysis was conducted on a sample of 359 Italian nurses. The results confirmed the mediation role of surface acting and showed that both age and seniority have moderating effects so that in conditions of high emotional load, older and more experienced nurses show higher levels of surface acting, and in conditions of high surface acting, younger and less experienced nurses show lower levels of perceived health. In conclusion, surface acting seems a stressor for younger nurses, not yet used to the weight of faking emotions, while the perceived emotional load seems a stressor for older and more experienced nurses. Each result highlights the importance of providing emotional regulation skills training and support to reduce the psychological impact of emotional demands on nurses

Volcanogenic particulates and gases from Etna volcano (Italy)

Volcanic emissions represent one of the most relevant natural sources of trace elements to the troposphere. Due to their potential toxicity they may have important environmental impacts from the local to the global scale and they can severely affect the atmospheric and terrestrial environment also at timescales ranging from a few to million years. Etna volcano is known as one of the largest global contributors of magmatic gases (CO2, SO2, and halogens) and particulate matter, including some toxic trace elements. The aim of this study was to characterize the chemical composition and the mineralogical features of the volcanogenic aerosol passively emitted from Mt. Etna. Nine samples were collected by using the filtration technique at different sites on summer 2010 and 2011. Chemical and mineralogical analyses allowed to discriminate two main constituents: the first is mainly referable to the silicate component in the volcanic plume, like lithic and juvenile fragments, crystals (e.g., plagioclases, pyroxenes, oxides) and shards of volcanic glass; the second one is linked to the soluble components like sulfosalts or halide minerals (sulfates, chlorides and fluorides). These investigations are especially important in the study area because the summit of Mt. Etna is yearly visited by nearly one hundred thousand tourists that are exposed to potentially harmful compounds

Biological control of peach fungal pathogens by commercial products and indigenous yeasts.

The potential use of the commercial biocontrol products Serenade (Bacillus subtilis QST-713) and Trichodex (Trichoderma harzianum Rifai strain T39) to inhibit the postharvest pathogenic molds Penicillium crustosum and Mucor circinelloides was investigated. Both products exhibited antagonistic activity in vitro against the pathogens, reducing their growth at different levels. In addition, epiphytic yeasts isolated from peaches were identified as Candida maltosa, Pichia fermentans, and Pichia kluyveri by PCR-restriction fragment length polymorphism of internal transcribed spacer regions and screened for antagonistic activity against the same molds. The efficacy of biocontrol in vitro was dependent on the concentration of the yeast cells. Optimal yeast concentrations were above 10(7) CFU ml(-1). However, C. maltosa and P. fermentans were more effective than P. kluyveri in inhibiting molds. The exclusion of antifungal metabolite production and direct competition for nutrients or space with the pathogens was proposed as the mechanism of biocontrol. Application of biocontrol agents directly on artificially wounded peach fruits significantly reduced the incidence of mold rot during storage at 20 degrees C

New data on the exploitation of obsidian in the mediterranean basin: The harbour of pyrgi and the trade in neolithic age

The contribution shows the first results of ongoing research on the origins and prehistoric assumptions of the well-known Etruscan and Roman harbour of Pyrgi, an ancient Ceretan harbour in southern Etruria. In the light of recent land and submarine investigations, traces of ancient frequentations and contacts dating back to the Neolithic era are emerging when the coastal morphology and environmental characteristics of the site were very different from the current ones. The Etruscan port of Pyrgi, which continues its historical history in Roman and Medieval times, appears as the heir of one or more landing points frequented perhaps already in the Middle Neolithic. As part of this contribution, around 60 obsidian finds (waste resulting from the manufacture of arrowheads) were analyzed using the LA-ICP-MS technique (Laser Ablation Inductively Coupled Plasma Mass Spectrometry). The comparison between the data obtained on the archaeological finds and the bibliographic data relating to the geological obsidians of the peri-Tyrrhenian area allowed the identification of the provenance of the finds. In particular, most of the finds can be attributed to the Aeolian area, highlighting the leading role played by the Aeolian archipelago in the development of trade of this material. Other sources of supply have been identified on the island of Palmarola and in Sardinia (Monte Arci) although with a lower incidence. The discovery of numerous findings in obsidian from overseas, which took place in the area immediately surrounding Pyrgi, offers different suggestions about the origin of the docking place, with traces of centuries-old frequentation, extended from the Neolithic to the modern era

Etna International Training School of Geochemistry. Science meets Practice

Also this year, the “Etna International Training School of Geochemistry. Science meets practice” took place at Mt. Etna, now in its fourth edition. The school was hosted in the historical Volcanological Observatory “Pizzi Deneri”, one of the most important sites of the INGV - Osservatorio Etneo for geochemical and geophysical monitoring. Mount Etna, located in eastern Sicily, is the largest active volcano in Europe and one of the most intensely degassing volcanoes of the world [Allard et al., 1991; Gerlach, 1991]. Mt Etna emits about 1.6 % of global H2O fluxes from arc volcanism [Aiuppa et al., 2008] and 10 % of global average volcanic emission of CO2 and SO2 [D’Alessandro et al., 1997; Caltabiano et al., 2004; Aiuppa et al., 2008; Carn et al., 2017]. Furthermore, Gauthier and Le Cloarec, [1998] underscored that Mt. Etna is an important source of volcanic particles, having a mass flux of particle passively released from the volcano during non-eruptive period estimated between 7 to 23 tons/day [Martin et al., 2008; Calabrese et al., 2011]. In general, Etna is considered to be still under evolution and rather ‘friendly’, which, along with the above, makes it a favorable natural laboratory to study volcanic geochemistry. The Observatory Pizzi Deneri was sponsored by Haroun Tazieff, and it was built in 1978 by the CNR - International Institute of Volcanology under the direction of Prof. Letterio Villari. It is located at the base of the North-East crater (2,850 m a.s.l.), near the Valle del Leone and it was built on the rim of the Ellittico caldera. A picturesque building, consisting of two characteristics domes in front of the breath-taking panorama of the summit craters. Even though it is quite spartan as an accommodation facility, the dormitories, kitchen, seminar room and laboratory are well equipped. In other words, the Pizzi Deneri observatory is a unique place close to the top of the most active volcano of Europe. The observatory lies in a strategic location making it one of the most important sites for monitoring, research and dissemination of the scientific culture. After six field multidisciplinary campaigns (2010-2015) organized by a group of researchers of several institutions (INGV of Palermo, Catania, Naples, Bologna; Universities of Palermo, Florence, Mainz, Heidelberg), the idea of sharing and passing on the experience to the new generation of students has materialized, and the “Etna International Training School of Geochemistry. Science meets practice” was born in 2016. The four editions of the school were partially funded by INGV of Palermo and Catania, European Geoscience Union (EGU), Società Geochimica Italiana (SoGeI) and Associazione Naturalistica Geode. The conceptual idea of the school is to share scientific knowledge and experiences in the geochemical community, using local resources with a low-cost organization in order to allow as many students as possible access to the school. The “Etna International Training School of Geochemistry. Science meets practice” is addressed to senior graduate students, postdoctoral researchers, fellows, and newly appointed assistant professors, aiming to bring together the next generation of researchers active in studies concerning the geochemistry and the budget of volcanic gases. Introduce the participants with innovative direct sampling and remote sensing techniques. Furthermore, it gives young scientists an opportunity to experiment and evaluate new protocols and techniques to be used on volcanic fluid emissions covering a broad variety of methods. The teaching approach includes theoretical sessions (lectures), practical demonstrations and field applications, conducted by international recognized geochemists. We thank all the teachers who helped to make the school possible, among these: Tobias Fischer (University of New Mexico Albuquerque), Jens Fiebig (Institut für Geowissenschaften Goethe-Universität Frankfurt am Main), Andri Stefansson (University of Iceland, Institute of Earth Sciences), Mike Burton (University of Manchester), Nicole Bobrowski (Universität Heidelberg Institute of Environmental Physics and Max Planck Institute for Chemistry), Alessandro Aiuppa (Università di Palermo), Franco Tassi (Università di Firenze), Walter D’Alessandro (INGV of Palermo), Fatima Viveiros (University of the Azores). Direct sampling of high-to-low temperature fumaroles, plume measurement techniques (using CO2/SO2 sensors such as Multi-GAS instruments, MAX-DOAS instruments and UV SO2 cameras, alkaline traps and particle filters), measurement of diffuse soil gas fluxes of endogenous gases (CO2, Hg0, CH4 and light hydrocarbons), sampling of mud volcanoes, groundwaters and bubbling gases. Sampling sites include the active summit craters, eruptive fractures and peripheral areas. The students have shown an active participation both to the lessons and the fieldworks. Most of them describe the school as formative and useful experience for their future researches. Their enthusiasm is the real engine of this school

Etna International Training School of Geochemistry. Science meets Practice

Also this year, the \u201cEtna International Training School of Geochemistry. Science meets practice\u201d took place at Mt. Etna, now in its fourth edition. The school was hosted in the historical Volcanological Observatory \u201cPizzi Deneri\u201d, one of the most important sites of the INGV - Osservatorio Etneo for geochemical and geophysical monitoring. Mount Etna, located in eastern Sicily, is the largest active volcano in Europe and one of the most intensely degassing volcanoes of the world [Allard et al., 1991; Gerlach, 1991]. Mt Etna emits about 1.6 % of global H2O fluxes from arc volcanism [Aiuppa et al., 2008] and 10 % of global average volcanic emission of CO2 and SO2 [D\u2019Alessandro et al., 1997; Caltabiano et al., 2004; Aiuppa et al., 2008; Carn et al., 2017]. Furthermore, Gauthier and Le Cloarec, [1998] underscored that Mt. Etna is an important source of volcanic particles, having a mass flux of particle passively released from the volcano during non-eruptive period estimated between 7 to 23 tons/day [Martin et al., 2008; Calabrese et al., 2011]. In general, Etna is considered to be still under evolution and rather \u2018friendly\u2019, which, along with the above, makes it a favorable natural laboratory to study volcanic geochemistry. The Observatory Pizzi Deneri was sponsored by Haroun Tazieff, and it was built in 1978 by the CNR - International Institute of Volcanology under the direction of Prof. Letterio Villari. It is located at the base of the North-East crater (2,850 m a.s.l.), near the Valle del Leone and it was built on the rim of the Ellittico caldera. A picturesque building, consisting of two characteristics domes in front of the breath-taking panorama of the summit craters. Even though it is quite spartan as an accommodation facility, the dormitories, kitchen, seminar room and laboratory are well equipped. In other words, the Pizzi Deneri observatory is a unique place close to the top of the most active volcano of Europe. The observatory lies in a strategic location making it one of the most important sites for monitoring, research and dissemination of the scientific culture. After six field multidisciplinary campaigns (2010-2015) organized by a group of researchers of several institutions (INGV of Palermo, Catania, Naples, Bologna; Universities of Palermo, Florence, Mainz, Heidelberg), the idea of sharing and passing on the experience to the new generation of students has materialized, and the \u201cEtna International Training School of Geochemistry. Science meets practice\u201d was born in 2016. The four editions of the school were partially funded by INGV of Palermo and Catania, European Geoscience Union (EGU), Societ\ue0 Geochimica Italiana (SoGeI) and Associazione Naturalistica Geode. The conceptual idea of the school is to share scientific knowledge and experiences in the geochemical community, using local resources with a low-cost organization in order to allow as many students as possible access to the school. The \u201cEtna International Training School of Geochemistry. Science meets practice\u201d is addressed to senior graduate students, postdoctoral researchers, fellows, and newly appointed assistant professors, aiming to bring together the next generation of researchers active in studies concerning the geochemistry and the budget of volcanic gases. Introduce the participants with innovative direct sampling and remote sensing techniques. Furthermore, it gives young scientists an opportunity to experiment and evaluate new protocols and techniques to be used on volcanic fluid emissions covering a broad variety of methods. The teaching approach includes theoretical sessions (lectures), practical demonstrations and field applications, conducted by international recognized geochemists. We thank all the teachers who helped to make the school possible, among these: Tobias Fischer (University of New Mexico Albuquerque), Jens Fiebig (Institut f\ufcr Geowissenschaften Goethe-Universit\ue4t Frankfurt am Main), Andri Stefansson (University of Iceland, Institute of Earth Sciences), Mike Burton (University of Manchester), Nicole Bobrowski (Universit\ue4t Heidelberg Institute of Environmental Physics and Max Planck Institute for Chemistry), Alessandro Aiuppa (Universit\ue0 di Palermo), Franco Tassi (Universit\ue0 di Firenze), Walter D\u2019Alessandro (INGV of Palermo), Fatima Viveiros (University of the Azores). Direct sampling of high-to-low temperature fumaroles, plume measurement techniques (using CO2/SO2 sensors such as Multi-GAS instruments, MAX-DOAS instruments and UV SO2 cameras, alkaline traps and particle filters), measurement of diffuse soil gas fluxes of endogenous gases (CO2, Hg0, CH4 and light hydrocarbons), sampling of mud volcanoes, groundwaters and bubbling gases. Sampling sites include the active summit craters, eruptive fractures and peripheral areas. The students have shown an active participation both to the lessons and the fieldworks. Most of them describe the school as formative and useful experience for their future researches. Their enthusiasm is the real engine of this school

Definition of analytical cleaning procedures for archaeological pottery from underwater environments: The case study of samples from Baia (Naples, South Italy)

Abstract This work is focused on a multidisciplinary study of 13 pottery fragments collected in the submerged archaeological site of Baia (Naples, Italy). Founded by the Romans in the 1st century B.C., this archaeological area represents one of the greatest evidences of Roman architecture and it includes ancient ruins whose structures range from maritime villas and imperial buildings. Several diagnostic tests were carried out in order to characterize the archaeological materials, their structure and properties, as well as the alteration and degradation products. Degradation forms in seawater imply not only a variation in the physico-mechanical and chemical properties of the material but also an aesthetic damage, due to superficial deposits, which can lead to the illegibility of the artefacts. In this context, it is crucial to determine to what extent these decay factors, mainly attributable to biological growth, could affect the durability of pottery and what are the effects of cleaning procedures. The work offers further elements to obtain new insights into the underwater cultural heritage field and in the function of ceramic matter, especially related to several applications in technology and in the adoption of strategies for suitable conservation procedures

Development of an optimized protocol for NMR metabolomics studies of human colon cancer cell lines and first insight from testing of the protocol using DNA G-quadruplex ligands as novel anti-cancer drugs

The study of cell lines by nuclear magnetic resonance (NMR) spectroscopy metabolomics represents a powerful tool to understand how the local metabolism and biochemical pathways are influenced by external or internal stimuli. In particular, the use of adherent mammalian cells is emerging in the metabolomics field in order to understand the molecular mechanism of disease progression or, for example, the cellular response to drug treatments. Hereto metabolomics investigations for this kind of cells have generally been limited to mass spectrometry studies. This study proposes an optimized protocol for the analysis of the endo-metabolome of human colon cancer cells (HCT116) by NMR. The protocol includes experimental conditions such as washing, quenching and extraction. In order to test the proposed protocol, it was applied to an exploratory study of cancer cells with and without treatment by anti-cancer drugs, such as DNA G-quadruplex binders and Adriamycin (a traditional anti-cancer drug). The exploratory NMR metabolomics analysis resulted in NMR assignment of all endo-metabolites that could be detected and provided preliminary insights about the biological behavior of the drugs tested